DNA microarrays provide a powerful approach for measuring gene expression on a genomic scale, allowing researchers to visualize changes in gene expression as a function of development, experience, disease, injury or physiological events. To facilitate the application of microarray technologies to critical problems in neuroscience, NINDS and NIMH in 2002 launched a consortium of three centers offering DNA microarrays and related services to the neuroscience community. The consortium provides standard DNA microarrays and services to all NINDS- and NIMH-funded investigators, and has developed a centralized database and analysis website that captures and archives MIAME-compliant data for experiments run through the consortium. This database provides a resource for individual investigators as well as a growing public set of microarray results relevant to basic and translational neurosciences. We propose here to continue as an integral component of this consortium, offering microarray platforms complementary to those provided by the other centers, and expanding the scope of consortium services to provide support at all stages of a microarray experiment. At the stage of sample preparation, we have established a new laser microdissection facility to meet the specialized needs of neuroscientists using microarrays to analyze specific populations of neural cells, small brain regions, or subcellular domains. Coordination with the other centers will ensure that samples prepared in the laser microdissection facility are suitable for analysis on any of the microarray platforms offered by the consortium. To extend support beyond the initial collection of microarray data, we propose to expand the tools and guidance available through the consortium website to assist investigators in analyzing and interpreting their own or public microarray results. Particular emphasis will be on tools to help investigators move beyond a simple list of differentially expressed genes to interpretations of the functional or diagnostic implications of the results. In collaboration with others in the consortium, we will continue research and development programs to enhance the representation on consortium arrays of transcripts involved in nervous system development, physiology and diseases, and to populate the consortium database with expression data for human and mouse nervous systems assayed across a series of developmental time points and brain regions on multiple microarray platforms. The proposed services build on a strong infrastructure and operating procedures developed in the first two years of the consortium to increase access of neuroscientists to established and emerging microarray technologies, and to enhance the value of those technologies in neuroscience research.